Method of making pulleys



Jan. 3, 1950 F. ZATYKO 2,493,053

METHOD OF MAKING PULLEYS Filed Aug. 9, 1947 4 Sheets-Sheet 1 INVENTOR. Frank Zatyko 9 V IL Y ZZEYS Jan. 3, 1950 F. ZATYKO 2,493,053

METHOD OF MAKINGPULLEYS Filed Aug. 9, 1947 4 Sheets-Sheet 2 IN V EN TOR.

Frank Zaiyka BY vqm ATTORNEYS Jan. 3, 1950 F. ZATYKO METHOD OF MAKING PULLEYS Filed Aug. 9, 1947 4 Sheets-Sheet 3 INVENTOR. Frank Zmiyko ATTORNEYS .Fan. 3 1950 F. ZATYKO 2,493,053

METHOD OF MAKING PULLEYS Filed Aug. 9, 1947 4 Sheets-Sheet 4 INVENTOR. Fwmnk Zn afiykv ATTORNEYS Patented Jan. 3, 1950 UNITED STATES PATENT METHOD OF MAKING PULLEYS Frank Zatyko, Cleveland, Ohio Application August 9, 1947, Serial No. 767,670

3 Claims.

The'present invention relates to a method for making pulleys and more particularly to a method for making pulleys from sheet metal by stamping operations alone.

In the past, pulleys constructed from sheet metal were either spun on a lathe to form the flanges or were stamped in two separate parts, each having a flange around its periphery, the two parts then being secured together by spot welding, riveting or the like to form the finished pulley.

The method of spinning sheet metal on a lathe to form a pulley is tedious and time consuming and therefore costly, and the method of stamping two separate parts followed by welding or riveting them together is not only time consuming and expensive but the finished pulley does not have the strength which can be attained when the pulley is made in a single piece.

According to the present invention the pulley is made in a single piece from sheet metal by stamping operations alone, thereby avoiding the disadvantages mentioned above.

It is, therefore, an object of this invention to provide a method for making pulleys from sheet metal by stamping alone.

A further object is to provide a novel method for making pulleys in a single piece from sheet metal without spinning and without the need for welding or riveting a plurality of parts together.

Other objects and advantages will be apparent from the following detailed description of the method in which particular reference will be made to the accompanying drawings and in which Figures 1 to 6 inclusive show the successive stages in this process of stamping a pulley from a sheet metal blank, each view being partially in elevation and partially in vertical cross-section.

Figure 7 is a vertical cross-section of the stamping dies just before the stamping operation for forming the inner pulley flange as shown in Figure 5,

Figure 8 is a vertical cross-sectional view of the dies similar to Figure 7 but showing the dies immediately after the stamping operation has been carried out, and

Figure 9 is a vertical cross-section of the dies immediately after carrying out the final stamping operation.

With reference to Figures 1 to 6 inclusive, a piece of sheet metal is first stamped to form a cylindrical cup-shaped blank ll, having a base or web l2 as shown in Figure 1. The blank II is then stamped and drawn to form the outwardly 2 ,f flared flange [3 as shown in Figure 2.; This operation also reduces the diameter of the blank and increases its length or depth. The depth of the blank at this stage, i. e. the distance from the web 12 to the flange l3 determines to a large extent, though not exclusively, the finallocation of the web with respect to the groove pf .the finished pulley. The next operation, as. shown in Figure 3 consists in spreading the flange, I3 to correspond with the outer flange of the finished pulley. The blank H is then stamped shown in Figure 4 to trim the edge of the flange l3 and to provide a rounded edge. This completes the stamping operation for forming the outer flange of the pulley and the blank I I, at this stagewill be termed a preformed cylindrical cup-shaped blank. 3

Figure 5 shows an annular bulge I4 which is formed around the cylindrical wall of the blank I i and which is ultimately formed into the inner flange [5 of the pulley, as shown in Figure 6.

The operation for forming thebulge I l is car-- ried out by applying pressure to the base I2 of the blank II, and at the same time by applying outward radial pressure against the cylindrical wall of the blank I I at the point where the bulge I4 is to be formed. The manner of carrying out this operation will be more fully describedhereinafter.

Figure 6 shows the finished pulley inwhich the bulge I 4 has been crimped together to form-the flange I 5; the flanges l3 and l5v forming the pulley groove !6.

bulge I4 to fold the metal flat upon itself the manner shown. As shown in Figure 6 the base oryweb not depending upon the use for which the pulley isdeslgned. The pulleyshown in Figure 6 is especially designed for use as a fan-belt pulleyin automobiles.

With reference to Figure '7 a stamping press is 5 shown which includes a die holder 20 and a form punch 2| removably secured thereto'in any conventional manner. to receive the flange l3 of the blank H after it has been preformed as seen in Figure 4 -A pair-- of semi-circular slide form blocks 22, which con stitute a split ring assembly, are sliolably mounted on the holder '20. A portion ofthe blocksare.

To accomplish this, pressureis applied on opposite sides of the crown of the' in The form punch}! is shaped take their open or retracted position, as shown in Figure 1-,, bythesis/tion of springs 25. The springs 2i cooperate with cam heel blocks 26 and the heads of bolts 21 which are secured to the slide form blocks 22 in the manner shown. When the.

punch holder 23 is lowered, the form blocks 22 are drawn together by cams 28 to the position shownin Figure 8. During this operation the cams 28. strike the tapered or conical surface 22a of the slide form blocks 22 and force them into the closed position, thus gripping blank I I about the flange II. The cam heel blocks 26 act as bearing surfaces for the earns 28 when they are lowered. The ring-24 is recessed at 24a to receive the top otblianlr I}.

the slide ,formbl'ocks 22 are each provided with annular recesses "22b for shaping the lowerhalf eiithebulge "while the form ring 24 is provided witha similar'annularrecess- 2 th which serves as a mold icr the upper half of the bulge I4.

The punch 21' which engages the lower portion of blank H is provided with a block of rubber- 29 as shown in Figure '7' which acts as an expander as hereinafter described. This rubber uses '29; is made of dense rubber of so-called "bumps! stock,for its equivalent which has a toughness and-i resiliency corresponding to the commonly known vulcanized tire-tread stock. mdiametei of the rubber block 29* is substan tially the same as the internal diameter ofthe blank N so that the blank canbe easily placed thereon. However; the-height of the-rubber block fiiesuch that when; the blank II- is in place as shown in Figure- Ltheflange I 3 thereofwill be spaced slightlyirom the corresponding surface of the-formpunoh 2-I for purposes-described hereinwhen Figure 8* showsthe' position of theelements at conclusion of the operation for forming the bulge It, asshown in Figure 5.

hrstarting this operation the stamping deviceappears as shown in Figure '7. When the-punch holdes zi is lowered the cams 28 draw theslide blocks 22 together.- Thus the inner edge of blocks will strike theupper surface of theflange I4 and=by=a camming-action, will draw the blink II! downward till it is seated on the form punehd i thuscom-pressing the'rubber-block soit will be engaged snugly at all points against the innen surfacaofiblanlc I I'. At the same time the formning Hidesc'ends-and fitsover the-blank I-I andlexertspmssureuponthe-base- I l of'the-bl'ank tending tocrushthe cylindricalwalls. However;

tmrubber blockwprevents the walls from bend ing inwardlyduetathe-initial compression-of the;

bloclcas: well as the further compression by the formiriag fl; The-rubber block-29will bulge and thus force thewalls of the-blankoutwardly and 1 pushes. the walls of blank II- outwardly as it is:

bang-crushed; thus shaping the blank as shown It isto be particularly noted that the bulgew-isn f rm cmy by. the radial presmended onthe cylindrical walls by-therubber block 29 but also by the pressure exerted by the form ring '24 on the base I2 as it descends and tends to crush the blank I I. The principal function of the rubber block 29 is to trigger the walls of the blank I I as they are crushed by the form ring 24 and thus start their outward bending. However, the rubber block 29 continues to exert some pressure on the walls all through this operation so that the metal is pressed firmly into the recesses 22b and 24b thus forming a smooth uniform bulge in the walls.

After the bulge I4 has been formed, the next step is to crimp the bulge so as to form the inner flange I5 as shown in Figure 6. This is accomplished by stamping the bulged blank II in the manner shown in Figure 9. In this view many of the elements are the same as those shown in Figures 7 and 8 and serve the same purpose. However, those elements which stamp or press the blank II are different. A form punch 31 is mounted on the die holder 20 and is shaped to support the blank I I- around the outer flange I3. The form punch iii-is provided with an axial hole 3| which is adapted to receive a punch as described further hereinafter. Another hole 32 is provided in the form punch 38' spaced from the axial hole 3i; for purposes described below. The slide form blocks 33, which are operated and controlled in the same manner as in Figures 7 and 8, are shaped to cooperate with the form punch so as to grip the flange I3. of the blank when the press is actuated. However, the blocks 33 are provided with an. inwardly'slopmgconical surface 33c around the centerto receive and crimp the lowerhalf ofbulge' I4;

A form ring 34 is secured to the punch holder 23" and is provided with an outwardly extending. conical surface 3'4a' adapted to cooperate with the surface 33a-toreceive and crimp the upper half of the bulge I4 to form the inner flange I5. The form ring 34* is also provided with a centrally' located depression 34b to receive the base- I2 or web of the blank I:I. Two punches 35 and 36 are provided" in the; depression 341; to cooperate with holes 3I- and 32' respectively for punching holes in the base I2 of the. blank; The" central-hole which is'cut out by the punch 35 enables the-finishedpulley to be mounted on a shaft. or otherrotatable element'and' the smaller hole. out outby'the punch Sbis for receiving a locking, bolt or the like..

In, operation, the blank II' which has been stamped to provide thebulge If as shown in Fig,- ure 5 is placed upon the form punch 30 and the punch holder is lowered- The slide. form blocks 33'are contracted by means ofthe cams 28 so. as. to" grip. the flange I3 of the blank. I I. At. the. same time theform ring. 3d. engages the, base of the. base I2. of the blank in the. depressionsub as well as the bulge Hr on the conical surface 342: and. crushesithe bulge against. the conicaL surface 33a of" the blbcks 33. By this operation. the bulge I4 is transformed into. the. inner, flange I5 as shown in Figure 6; Near. the endiof. the

' downward travel of" the punch holder. 23 thepunches 35* and 36 will punchthe holes. as re.--

ferred to above thus. completing the pulley...

If'desired a single. stamping, pressmaybe. used; for all the various operations in forming. the pulley, but this necessitates changing the, form punch, slide.form blocks and formring to perform. any oneparticular. operation. Therefore.

it preferable. to, have. a, series. 01 stamping. presses, each. one adapted. to. perform. a single operation on the blanks. In this instance the blanks proceed from one press to the next as the various operations are completed.

Various gauges of sheet steel may be shaped according to the present invention. For example 20 gauge up to 12 gauge steel may be shaped without difliculty. Gauges lighter than 20 gauge will sometimes tear or split during the stamping operations due to lower tensile strength and gauges heavier than 12 gauge will not respond at all times to the radial pressure exerted by the rubber block 29.

While the invention has been described with regard to a particular operation, it will be understood that various modifications will be obvious to one skilled in the art. The invention therefore, is not limited by the description thereof but is defined by the appended claims.

What is claimed is:

1. The method of forming a V-belt pulley from sheet metal comprising the steps of forming from a blank of said metal a seamless flanged cup having a wall of substantially uniform thickness, the flange on said cup constituting a first flange of a V-belt groove and being formed at an obtuse angle to the wall of said cup; simultaneously transmitting an axial compressive force along said cup wall and applying an outward transaxial force to an annular portion of said cup wall to form an annular bulge in the wall of said cup above said flange, said axial and transaxial forces being simultaneously exerted while confining said first flange, the edge thereof, and an annular portion of said cup wall intermediate said flange and said bulge, said bulge taking up an axial length of the wall of said cup substantially equal to twice the length of said first flange; and, while confining said first flange, the edge thereof, and said intermediate annular wall portion, subjecting the annular portion of the bulge which is remote from said first flange to a force pressing said remote portion toward said flange and simultaneously subjecting the annular portion of said bulge adjacent said first flange to a force opposing that applied to said remote portion in order to fold said bulge along a median a annular fold line and to form a second flange at an acute angle to said cup wall, said acute angle to said second flange being complementary to the obtuse angle of said first flange to form a V-belt groove, said groove being accurately sized by the confining of said first flange, its edge and the intermediate wall portion during the said bulging and folding operations.

2. The method of forming a V-belt pulley from sheet metal comprising the steps of drawing a seamless flanged cup having a wall of substantially uniform thickness and a bead on the edge of said flange, the flange constituting a first flange of a V-belt groove and being formed at an obtuse angle to the wall of said cup; simultaneously transmitting an axial compressive force along said cup wall and applying an outward transaxial force to an annular portion of said cup wall to form an annular bulge in the wall of said cup above said flange, said axial and transaxial forces being simultaneously exerted while confining said first flange, said bead and an annular portion of said cup wall intermediate said flange and said bulge, and, while confining said first flange, said bead, and said intermediate annular wall portion, applying compressive forces to the sides of said bulge and folding said bulge on a circular fold line concentric with and spaced from said bead to form a second flange having a wall adjacent said first flange and at an angle complementary thereto.

3. The method of forming a V-belt pulley form sheet metal comprisin the steps of forming from a blank of said metal a seamless cup having a bottom, a wall of substantially uniform thickness, and a flange integral with said wall, the flange on said cup constituting a first flange of a V-belt groove and being formed at an obtuse angle to the wall of said cup; simultaneously transmitting an axial compressive force along said cup wall and applying an outward transaxial force to an annular portion of said cup wall to form an annular bulge in the wall of said cup above said flange, said axial and transaxial forces being simultaneously exerted while confinin said first flange, the edge thereof, and an annular portion of said cup wall intermediate said flange and said bulge, said bulge taking up an axial length of the wall of said cup substantially equal to twice the length of said first flange; while confining said first flange, the edge thereof, and said intermediate annular wall portion, subjecting the annular portion of the bulge which is remote from said first flange to a force pressing said remote portion toward said flange and simultaneously subjecting the annular portion of said bulge adjacent said first flange to a force opposing that applied to said remote portion in order to fold said bulge along a median annular fold line to form a second flange at an acute angle to said cup wall, said acute angle of said second flange being complementary to the obtuse angle of said first flange to form a V-belt groove; and fabricating said cup bottom to provide a web for said pulley and means for locating said web on a hub concentric with said V-belt groove.

FRANK ZATYKO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,609,380 Murray et a1 Dec. 7, 1926 1,711,182 Shrum Apr. 30, 1929 1,756,592 Harrison Apr. 29, 1930 1,766,098 Booth June 24, 1930 1,928,911 Riemenschneider et al. Oct. 3, 1933 2,006,691 Giesler July 2, 1935 2,092,571 Cole Sept. 7, 1937 2,132,002 Hight Oct. 4, 1938 2,162,735 Lyon June 20, 1939 2,330,228 Lyon Sept. 28, 1943 2,358,984 Lyon Sept. 26, 1944 

